#include <linux/mm_inline.h>
#include <linux/page_cgroup.h>
#include <linux/cpu.h>
+#include <linux/oom.h>
#include "internal.h"
#include <asm/uaccess.h>
+#include <trace/events/vmscan.h>
+
struct cgroup_subsys mem_cgroup_subsys __read_mostly;
#define MEM_CGROUP_RECLAIM_RETRIES 5
struct mem_cgroup *root_mem_cgroup __read_mostly;
#ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
/* Turned on only when memory cgroup is enabled && really_do_swap_account = 1 */
int do_swap_account __read_mostly;
-static int really_do_swap_account __initdata = 1; /* for remember boot option*/
+
+/* for remember boot option*/
+#ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP_ENABLED
+static int really_do_swap_account __initdata = 1;
+#else
+static int really_do_swap_account __initdata = 0;
+#endif
+
#else
#define do_swap_account (0)
#endif
MEM_CGROUP_STAT_PGPGIN_COUNT, /* # of pages paged in */
MEM_CGROUP_STAT_PGPGOUT_COUNT, /* # of pages paged out */
MEM_CGROUP_STAT_SWAPOUT, /* # of pages, swapped out */
- MEM_CGROUP_EVENTS, /* incremented at every pagein/pageout */
+ MEM_CGROUP_STAT_DATA, /* end of data requires synchronization */
+ /* incremented at every pagein/pageout */
+ MEM_CGROUP_EVENTS = MEM_CGROUP_STAT_DATA,
+ MEM_CGROUP_ON_MOVE, /* someone is moving account between groups */
MEM_CGROUP_STAT_NSTATS,
};
u64 threshold;
};
+/* For threshold */
struct mem_cgroup_threshold_ary {
/* An array index points to threshold just below usage. */
- atomic_t current_threshold;
+ int current_threshold;
/* Size of entries[] */
unsigned int size;
/* Array of thresholds */
struct mem_cgroup_threshold entries[0];
};
+struct mem_cgroup_thresholds {
+ /* Primary thresholds array */
+ struct mem_cgroup_threshold_ary *primary;
+ /*
+ * Spare threshold array.
+ * This is needed to make mem_cgroup_unregister_event() "never fail".
+ * It must be able to store at least primary->size - 1 entries.
+ */
+ struct mem_cgroup_threshold_ary *spare;
+};
+
+/* for OOM */
+struct mem_cgroup_eventfd_list {
+ struct list_head list;
+ struct eventfd_ctx *eventfd;
+};
+
static void mem_cgroup_threshold(struct mem_cgroup *mem);
+static void mem_cgroup_oom_notify(struct mem_cgroup *mem);
/*
* The memory controller data structure. The memory controller controls both
*/
spinlock_t reclaim_param_lock;
- int prev_priority; /* for recording reclaim priority */
-
/*
* While reclaiming in a hierarchy, we cache the last child we
* reclaimed from.
atomic_t refcnt;
unsigned int swappiness;
+ /* OOM-Killer disable */
+ int oom_kill_disable;
/* set when res.limit == memsw.limit */
bool memsw_is_minimum;
struct mutex thresholds_lock;
/* thresholds for memory usage. RCU-protected */
- struct mem_cgroup_threshold_ary *thresholds;
+ struct mem_cgroup_thresholds thresholds;
/* thresholds for mem+swap usage. RCU-protected */
- struct mem_cgroup_threshold_ary *memsw_thresholds;
+ struct mem_cgroup_thresholds memsw_thresholds;
+
+ /* For oom notifier event fd */
+ struct list_head oom_notify;
/*
* Should we move charges of a task when a task is moved into this
* mem_cgroup ? And what type of charges should we move ?
*/
unsigned long move_charge_at_immigrate;
-
/*
* percpu counter.
*/
struct mem_cgroup_stat_cpu *stat;
+ /*
+ * used when a cpu is offlined or other synchronizations
+ * See mem_cgroup_read_stat().
+ */
+ struct mem_cgroup_stat_cpu nocpu_base;
+ spinlock_t pcp_counter_lock;
};
/* Stuffs for move charges at task migration. */
*/
enum move_type {
MOVE_CHARGE_TYPE_ANON, /* private anonymous page and swap of it */
+ MOVE_CHARGE_TYPE_FILE, /* file page(including tmpfs) and swap of it */
NR_MOVE_TYPE,
};
/* "mc" and its members are protected by cgroup_mutex */
static struct move_charge_struct {
+ spinlock_t lock; /* for from, to */
struct mem_cgroup *from;
struct mem_cgroup *to;
unsigned long precharge;
struct task_struct *moving_task; /* a task moving charges */
wait_queue_head_t waitq; /* a waitq for other context */
} mc = {
+ .lock = __SPIN_LOCK_UNLOCKED(mc.lock),
.waitq = __WAIT_QUEUE_HEAD_INITIALIZER(mc.waitq),
};
+static bool move_anon(void)
+{
+ return test_bit(MOVE_CHARGE_TYPE_ANON,
+ &mc.to->move_charge_at_immigrate);
+}
+
+static bool move_file(void)
+{
+ return test_bit(MOVE_CHARGE_TYPE_FILE,
+ &mc.to->move_charge_at_immigrate);
+}
+
/*
* Maximum loops in mem_cgroup_hierarchical_reclaim(), used for soft
* limit reclaim to prevent infinite loops, if they ever occur.
/* for encoding cft->private value on file */
#define _MEM (0)
#define _MEMSWAP (1)
+#define _OOM_TYPE (2)
#define MEMFILE_PRIVATE(x, val) (((x) << 16) | (val))
#define MEMFILE_TYPE(val) (((val) >> 16) & 0xffff)
#define MEMFILE_ATTR(val) ((val) & 0xffff)
+/* Used for OOM nofiier */
+#define OOM_CONTROL (0)
/*
* Reclaim flags for mem_cgroup_hierarchical_reclaim
return mz;
}
+/*
+ * Implementation Note: reading percpu statistics for memcg.
+ *
+ * Both of vmstat[] and percpu_counter has threshold and do periodic
+ * synchronization to implement "quick" read. There are trade-off between
+ * reading cost and precision of value. Then, we may have a chance to implement
+ * a periodic synchronizion of counter in memcg's counter.
+ *
+ * But this _read() function is used for user interface now. The user accounts
+ * memory usage by memory cgroup and he _always_ requires exact value because
+ * he accounts memory. Even if we provide quick-and-fuzzy read, we always
+ * have to visit all online cpus and make sum. So, for now, unnecessary
+ * synchronization is not implemented. (just implemented for cpu hotplug)
+ *
+ * If there are kernel internal actions which can make use of some not-exact
+ * value, and reading all cpu value can be performance bottleneck in some
+ * common workload, threashold and synchonization as vmstat[] should be
+ * implemented.
+ */
static s64 mem_cgroup_read_stat(struct mem_cgroup *mem,
enum mem_cgroup_stat_index idx)
{
int cpu;
s64 val = 0;
- for_each_possible_cpu(cpu)
+ get_online_cpus();
+ for_each_online_cpu(cpu)
val += per_cpu(mem->stat->count[idx], cpu);
+#ifdef CONFIG_HOTPLUG_CPU
+ spin_lock(&mem->pcp_counter_lock);
+ val += mem->nocpu_base.count[idx];
+ spin_unlock(&mem->pcp_counter_lock);
+#endif
+ put_online_cpus();
return val;
}
}
static void mem_cgroup_charge_statistics(struct mem_cgroup *mem,
- struct page_cgroup *pc,
- bool charge)
+ bool file, int nr_pages)
{
- int val = (charge) ? 1 : -1;
-
preempt_disable();
- if (PageCgroupCache(pc))
- __this_cpu_add(mem->stat->count[MEM_CGROUP_STAT_CACHE], val);
+ if (file)
+ __this_cpu_add(mem->stat->count[MEM_CGROUP_STAT_CACHE], nr_pages);
else
- __this_cpu_add(mem->stat->count[MEM_CGROUP_STAT_RSS], val);
+ __this_cpu_add(mem->stat->count[MEM_CGROUP_STAT_RSS], nr_pages);
- if (charge)
+ /* pagein of a big page is an event. So, ignore page size */
+ if (nr_pages > 0)
__this_cpu_inc(mem->stat->count[MEM_CGROUP_STAT_PGPGIN_COUNT]);
- else
+ else {
__this_cpu_inc(mem->stat->count[MEM_CGROUP_STAT_PGPGOUT_COUNT]);
- __this_cpu_inc(mem->stat->count[MEM_CGROUP_EVENTS]);
+ nr_pages = -nr_pages; /* for event */
+ }
+
+ __this_cpu_add(mem->stat->count[MEM_CGROUP_EVENTS], nr_pages);
preempt_enable();
}
return mem;
}
-/*
- * Call callback function against all cgroup under hierarchy tree.
- */
-static int mem_cgroup_walk_tree(struct mem_cgroup *root, void *data,
- int (*func)(struct mem_cgroup *, void *))
+/* The caller has to guarantee "mem" exists before calling this */
+static struct mem_cgroup *mem_cgroup_start_loop(struct mem_cgroup *mem)
{
- int found, ret, nextid;
struct cgroup_subsys_state *css;
- struct mem_cgroup *mem;
+ int found;
- if (!root->use_hierarchy)
- return (*func)(root, data);
-
- nextid = 1;
- do {
- ret = 0;
+ if (!mem) /* ROOT cgroup has the smallest ID */
+ return root_mem_cgroup; /*css_put/get against root is ignored*/
+ if (!mem->use_hierarchy) {
+ if (css_tryget(&mem->css))
+ return mem;
+ return NULL;
+ }
+ rcu_read_lock();
+ /*
+ * searching a memory cgroup which has the smallest ID under given
+ * ROOT cgroup. (ID >= 1)
+ */
+ css = css_get_next(&mem_cgroup_subsys, 1, &mem->css, &found);
+ if (css && css_tryget(css))
+ mem = container_of(css, struct mem_cgroup, css);
+ else
mem = NULL;
+ rcu_read_unlock();
+ return mem;
+}
+
+static struct mem_cgroup *mem_cgroup_get_next(struct mem_cgroup *iter,
+ struct mem_cgroup *root,
+ bool cond)
+{
+ int nextid = css_id(&iter->css) + 1;
+ int found;
+ int hierarchy_used;
+ struct cgroup_subsys_state *css;
+
+ hierarchy_used = iter->use_hierarchy;
+
+ css_put(&iter->css);
+ /* If no ROOT, walk all, ignore hierarchy */
+ if (!cond || (root && !hierarchy_used))
+ return NULL;
+ if (!root)
+ root = root_mem_cgroup;
+
+ do {
+ iter = NULL;
rcu_read_lock();
- css = css_get_next(&mem_cgroup_subsys, nextid, &root->css,
- &found);
+
+ css = css_get_next(&mem_cgroup_subsys, nextid,
+ &root->css, &found);
if (css && css_tryget(css))
- mem = container_of(css, struct mem_cgroup, css);
+ iter = container_of(css, struct mem_cgroup, css);
rcu_read_unlock();
-
- if (mem) {
- ret = (*func)(mem, data);
- css_put(&mem->css);
- }
+ /* If css is NULL, no more cgroups will be found */
nextid = found + 1;
- } while (!ret && css);
+ } while (css && !iter);
- return ret;
+ return iter;
}
+/*
+ * for_eacn_mem_cgroup_tree() for visiting all cgroup under tree. Please
+ * be careful that "break" loop is not allowed. We have reference count.
+ * Instead of that modify "cond" to be false and "continue" to exit the loop.
+ */
+#define for_each_mem_cgroup_tree_cond(iter, root, cond) \
+ for (iter = mem_cgroup_start_loop(root);\
+ iter != NULL;\
+ iter = mem_cgroup_get_next(iter, root, cond))
+
+#define for_each_mem_cgroup_tree(iter, root) \
+ for_each_mem_cgroup_tree_cond(iter, root, true)
+
+#define for_each_mem_cgroup_all(iter) \
+ for_each_mem_cgroup_tree_cond(iter, NULL, true)
+
static inline bool mem_cgroup_is_root(struct mem_cgroup *mem)
{
* removed from global LRU.
*/
mz = page_cgroup_zoneinfo(pc);
- MEM_CGROUP_ZSTAT(mz, lru) -= 1;
+ /* huge page split is done under lru_lock. so, we have no races. */
+ MEM_CGROUP_ZSTAT(mz, lru) -= 1 << compound_order(page);
if (mem_cgroup_is_root(pc->mem_cgroup))
return;
VM_BUG_ON(list_empty(&pc->lru));
list_del_init(&pc->lru);
- return;
}
void mem_cgroup_del_lru(struct page *page)
return;
pc = lookup_page_cgroup(page);
- /*
- * Used bit is set without atomic ops but after smp_wmb().
- * For making pc->mem_cgroup visible, insert smp_rmb() here.
- */
- smp_rmb();
/* unused or root page is not rotated. */
- if (!PageCgroupUsed(pc) || mem_cgroup_is_root(pc->mem_cgroup))
+ if (!PageCgroupUsed(pc))
+ return;
+ /* Ensure pc->mem_cgroup is visible after reading PCG_USED. */
+ smp_rmb();
+ if (mem_cgroup_is_root(pc->mem_cgroup))
return;
mz = page_cgroup_zoneinfo(pc);
list_move(&pc->lru, &mz->lists[lru]);
return;
pc = lookup_page_cgroup(page);
VM_BUG_ON(PageCgroupAcctLRU(pc));
- /*
- * Used bit is set without atomic ops but after smp_wmb().
- * For making pc->mem_cgroup visible, insert smp_rmb() here.
- */
- smp_rmb();
if (!PageCgroupUsed(pc))
return;
-
+ /* Ensure pc->mem_cgroup is visible after reading PCG_USED. */
+ smp_rmb();
mz = page_cgroup_zoneinfo(pc);
- MEM_CGROUP_ZSTAT(mz, lru) += 1;
+ /* huge page split is done under lru_lock. so, we have no races. */
+ MEM_CGROUP_ZSTAT(mz, lru) += 1 << compound_order(page);
SetPageCgroupAcctLRU(pc);
if (mem_cgroup_is_root(pc->mem_cgroup))
return;
{
int ret;
struct mem_cgroup *curr = NULL;
+ struct task_struct *p;
- task_lock(task);
- rcu_read_lock();
- curr = try_get_mem_cgroup_from_mm(task->mm);
- rcu_read_unlock();
- task_unlock(task);
+ p = find_lock_task_mm(task);
+ if (!p)
+ return 0;
+ curr = try_get_mem_cgroup_from_mm(p->mm);
+ task_unlock(p);
if (!curr)
return 0;
/*
return ret;
}
-/*
- * prev_priority control...this will be used in memory reclaim path.
- */
-int mem_cgroup_get_reclaim_priority(struct mem_cgroup *mem)
-{
- int prev_priority;
-
- spin_lock(&mem->reclaim_param_lock);
- prev_priority = mem->prev_priority;
- spin_unlock(&mem->reclaim_param_lock);
-
- return prev_priority;
-}
-
-void mem_cgroup_note_reclaim_priority(struct mem_cgroup *mem, int priority)
-{
- spin_lock(&mem->reclaim_param_lock);
- if (priority < mem->prev_priority)
- mem->prev_priority = priority;
- spin_unlock(&mem->reclaim_param_lock);
-}
-
-void mem_cgroup_record_reclaim_priority(struct mem_cgroup *mem, int priority)
-{
- spin_lock(&mem->reclaim_param_lock);
- mem->prev_priority = priority;
- spin_unlock(&mem->reclaim_param_lock);
-}
-
static int calc_inactive_ratio(struct mem_cgroup *memcg, unsigned long *present_pages)
{
unsigned long active;
struct zone *zone,
enum lru_list lru)
{
- int nid = zone->zone_pgdat->node_id;
+ int nid = zone_to_nid(zone);
int zid = zone_idx(zone);
struct mem_cgroup_per_zone *mz = mem_cgroup_zoneinfo(memcg, nid, zid);
struct zone_reclaim_stat *mem_cgroup_get_reclaim_stat(struct mem_cgroup *memcg,
struct zone *zone)
{
- int nid = zone->zone_pgdat->node_id;
+ int nid = zone_to_nid(zone);
int zid = zone_idx(zone);
struct mem_cgroup_per_zone *mz = mem_cgroup_zoneinfo(memcg, nid, zid);
return NULL;
pc = lookup_page_cgroup(page);
- /*
- * Used bit is set without atomic ops but after smp_wmb().
- * For making pc->mem_cgroup visible, insert smp_rmb() here.
- */
- smp_rmb();
if (!PageCgroupUsed(pc))
return NULL;
-
+ /* Ensure pc->mem_cgroup is visible after reading PCG_USED. */
+ smp_rmb();
mz = page_cgroup_zoneinfo(pc);
if (!mz)
return NULL;
LIST_HEAD(pc_list);
struct list_head *src;
struct page_cgroup *pc, *tmp;
- int nid = z->zone_pgdat->node_id;
+ int nid = zone_to_nid(z);
int zid = zone_idx(z);
struct mem_cgroup_per_zone *mz;
int lru = LRU_FILE * file + active;
case 0:
list_move(&page->lru, dst);
mem_cgroup_del_lru(page);
- nr_taken++;
+ nr_taken += hpage_nr_pages(page);
break;
case -EBUSY:
/* we don't affect global LRU but rotate in our LRU */
}
*scanned = scan;
+
+ trace_mm_vmscan_memcg_isolate(0, nr_to_scan, scan, nr_taken,
+ 0, 0, 0, mode);
+
return nr_taken;
}
return false;
}
+/**
+ * mem_cgroup_check_margin - check if the memory cgroup allows charging
+ * @mem: memory cgroup to check
+ * @bytes: the number of bytes the caller intends to charge
+ *
+ * Returns a boolean value on whether @mem can be charged @bytes or
+ * whether this would exceed the limit.
+ */
+static bool mem_cgroup_check_margin(struct mem_cgroup *mem, unsigned long bytes)
+{
+ if (!res_counter_check_margin(&mem->res, bytes))
+ return false;
+ if (do_swap_account && !res_counter_check_margin(&mem->memsw, bytes))
+ return false;
+ return true;
+}
+
static unsigned int get_swappiness(struct mem_cgroup *memcg)
{
struct cgroup *cgrp = memcg->css.cgroup;
return swappiness;
}
-static int mem_cgroup_count_children_cb(struct mem_cgroup *mem, void *data)
+static void mem_cgroup_start_move(struct mem_cgroup *mem)
{
- int *val = data;
- (*val)++;
- return 0;
+ int cpu;
+
+ get_online_cpus();
+ spin_lock(&mem->pcp_counter_lock);
+ for_each_online_cpu(cpu)
+ per_cpu(mem->stat->count[MEM_CGROUP_ON_MOVE], cpu) += 1;
+ mem->nocpu_base.count[MEM_CGROUP_ON_MOVE] += 1;
+ spin_unlock(&mem->pcp_counter_lock);
+ put_online_cpus();
+
+ synchronize_rcu();
+}
+
+static void mem_cgroup_end_move(struct mem_cgroup *mem)
+{
+ int cpu;
+
+ if (!mem)
+ return;
+ get_online_cpus();
+ spin_lock(&mem->pcp_counter_lock);
+ for_each_online_cpu(cpu)
+ per_cpu(mem->stat->count[MEM_CGROUP_ON_MOVE], cpu) -= 1;
+ mem->nocpu_base.count[MEM_CGROUP_ON_MOVE] -= 1;
+ spin_unlock(&mem->pcp_counter_lock);
+ put_online_cpus();
+}
+/*
+ * 2 routines for checking "mem" is under move_account() or not.
+ *
+ * mem_cgroup_stealed() - checking a cgroup is mc.from or not. This is used
+ * for avoiding race in accounting. If true,
+ * pc->mem_cgroup may be overwritten.
+ *
+ * mem_cgroup_under_move() - checking a cgroup is mc.from or mc.to or
+ * under hierarchy of moving cgroups. This is for
+ * waiting at hith-memory prressure caused by "move".
+ */
+
+static bool mem_cgroup_stealed(struct mem_cgroup *mem)
+{
+ VM_BUG_ON(!rcu_read_lock_held());
+ return this_cpu_read(mem->stat->count[MEM_CGROUP_ON_MOVE]) > 0;
+}
+
+static bool mem_cgroup_under_move(struct mem_cgroup *mem)
+{
+ struct mem_cgroup *from;
+ struct mem_cgroup *to;
+ bool ret = false;
+ /*
+ * Unlike task_move routines, we access mc.to, mc.from not under
+ * mutual exclusion by cgroup_mutex. Here, we take spinlock instead.
+ */
+ spin_lock(&mc.lock);
+ from = mc.from;
+ to = mc.to;
+ if (!from)
+ goto unlock;
+ if (from == mem || to == mem
+ || (mem->use_hierarchy && css_is_ancestor(&from->css, &mem->css))
+ || (mem->use_hierarchy && css_is_ancestor(&to->css, &mem->css)))
+ ret = true;
+unlock:
+ spin_unlock(&mc.lock);
+ return ret;
+}
+
+static bool mem_cgroup_wait_acct_move(struct mem_cgroup *mem)
+{
+ if (mc.moving_task && current != mc.moving_task) {
+ if (mem_cgroup_under_move(mem)) {
+ DEFINE_WAIT(wait);
+ prepare_to_wait(&mc.waitq, &wait, TASK_INTERRUPTIBLE);
+ /* moving charge context might have finished. */
+ if (mc.moving_task)
+ schedule();
+ finish_wait(&mc.waitq, &wait);
+ return true;
+ }
+ }
+ return false;
}
/**
static int mem_cgroup_count_children(struct mem_cgroup *mem)
{
int num = 0;
- mem_cgroup_walk_tree(mem, &num, mem_cgroup_count_children_cb);
+ struct mem_cgroup *iter;
+
+ for_each_mem_cgroup_tree(iter, mem)
+ num++;
return num;
}
/*
+ * Return the memory (and swap, if configured) limit for a memcg.
+ */
+u64 mem_cgroup_get_limit(struct mem_cgroup *memcg)
+{
+ u64 limit;
+ u64 memsw;
+
+ limit = res_counter_read_u64(&memcg->res, RES_LIMIT);
+ limit += total_swap_pages << PAGE_SHIFT;
+
+ memsw = res_counter_read_u64(&memcg->memsw, RES_LIMIT);
+ /*
+ * If memsw is finite and limits the amount of swap space available
+ * to this memcg, return that limit.
+ */
+ return min(limit, memsw);
+}
+
+/*
* Visit the first child (need not be the first child as per the ordering
* of the cgroup list, since we track last_scanned_child) of @mem and use
* that to reclaim free pages from.
/* we use swappiness of local cgroup */
if (check_soft)
ret = mem_cgroup_shrink_node_zone(victim, gfp_mask,
- noswap, get_swappiness(victim), zone,
- zone->zone_pgdat->node_id);
+ noswap, get_swappiness(victim), zone);
else
ret = try_to_free_mem_cgroup_pages(victim, gfp_mask,
noswap, get_swappiness(victim));
return total;
}
-static int mem_cgroup_oom_lock_cb(struct mem_cgroup *mem, void *data)
-{
- int *val = (int *)data;
- int x;
- /*
- * Logically, we can stop scanning immediately when we find
- * a memcg is already locked. But condidering unlock ops and
- * creation/removal of memcg, scan-all is simple operation.
- */
- x = atomic_inc_return(&mem->oom_lock);
- *val = max(x, *val);
- return 0;
-}
/*
* Check OOM-Killer is already running under our hierarchy.
* If someone is running, return false.
*/
static bool mem_cgroup_oom_lock(struct mem_cgroup *mem)
{
- int lock_count = 0;
+ int x, lock_count = 0;
+ struct mem_cgroup *iter;
- mem_cgroup_walk_tree(mem, &lock_count, mem_cgroup_oom_lock_cb);
+ for_each_mem_cgroup_tree(iter, mem) {
+ x = atomic_inc_return(&iter->oom_lock);
+ lock_count = max(x, lock_count);
+ }
if (lock_count == 1)
return true;
return false;
}
-static int mem_cgroup_oom_unlock_cb(struct mem_cgroup *mem, void *data)
+static int mem_cgroup_oom_unlock(struct mem_cgroup *mem)
{
+ struct mem_cgroup *iter;
+
/*
* When a new child is created while the hierarchy is under oom,
* mem_cgroup_oom_lock() may not be called. We have to use
* atomic_add_unless() here.
*/
- atomic_add_unless(&mem->oom_lock, -1, 0);
+ for_each_mem_cgroup_tree(iter, mem)
+ atomic_add_unless(&iter->oom_lock, -1, 0);
return 0;
}
-static void mem_cgroup_oom_unlock(struct mem_cgroup *mem)
-{
- mem_cgroup_walk_tree(mem, NULL, mem_cgroup_oom_unlock_cb);
-}
static DEFINE_MUTEX(memcg_oom_mutex);
static DECLARE_WAIT_QUEUE_HEAD(memcg_oom_waitq);
+struct oom_wait_info {
+ struct mem_cgroup *mem;
+ wait_queue_t wait;
+};
+
+static int memcg_oom_wake_function(wait_queue_t *wait,
+ unsigned mode, int sync, void *arg)
+{
+ struct mem_cgroup *wake_mem = (struct mem_cgroup *)arg;
+ struct oom_wait_info *oom_wait_info;
+
+ oom_wait_info = container_of(wait, struct oom_wait_info, wait);
+
+ if (oom_wait_info->mem == wake_mem)
+ goto wakeup;
+ /* if no hierarchy, no match */
+ if (!oom_wait_info->mem->use_hierarchy || !wake_mem->use_hierarchy)
+ return 0;
+ /*
+ * Both of oom_wait_info->mem and wake_mem are stable under us.
+ * Then we can use css_is_ancestor without taking care of RCU.
+ */
+ if (!css_is_ancestor(&oom_wait_info->mem->css, &wake_mem->css) &&
+ !css_is_ancestor(&wake_mem->css, &oom_wait_info->mem->css))
+ return 0;
+
+wakeup:
+ return autoremove_wake_function(wait, mode, sync, arg);
+}
+
+static void memcg_wakeup_oom(struct mem_cgroup *mem)
+{
+ /* for filtering, pass "mem" as argument. */
+ __wake_up(&memcg_oom_waitq, TASK_NORMAL, 0, mem);
+}
+
+static void memcg_oom_recover(struct mem_cgroup *mem)
+{
+ if (mem && atomic_read(&mem->oom_lock))
+ memcg_wakeup_oom(mem);
+}
+
/*
* try to call OOM killer. returns false if we should exit memory-reclaim loop.
*/
bool mem_cgroup_handle_oom(struct mem_cgroup *mem, gfp_t mask)
{
- DEFINE_WAIT(wait);
- bool locked;
+ struct oom_wait_info owait;
+ bool locked, need_to_kill;
+ owait.mem = mem;
+ owait.wait.flags = 0;
+ owait.wait.func = memcg_oom_wake_function;
+ owait.wait.private = current;
+ INIT_LIST_HEAD(&owait.wait.task_list);
+ need_to_kill = true;
/* At first, try to OOM lock hierarchy under mem.*/
mutex_lock(&memcg_oom_mutex);
locked = mem_cgroup_oom_lock(mem);
* accounting. So, UNINTERRUPTIBLE is appropriate. But SIGKILL
* under OOM is always welcomed, use TASK_KILLABLE here.
*/
- if (!locked)
- prepare_to_wait(&memcg_oom_waitq, &wait, TASK_KILLABLE);
+ prepare_to_wait(&memcg_oom_waitq, &owait.wait, TASK_KILLABLE);
+ if (!locked || mem->oom_kill_disable)
+ need_to_kill = false;
+ if (locked)
+ mem_cgroup_oom_notify(mem);
mutex_unlock(&memcg_oom_mutex);
- if (locked)
+ if (need_to_kill) {
+ finish_wait(&memcg_oom_waitq, &owait.wait);
mem_cgroup_out_of_memory(mem, mask);
- else {
+ } else {
schedule();
- finish_wait(&memcg_oom_waitq, &wait);
+ finish_wait(&memcg_oom_waitq, &owait.wait);
}
mutex_lock(&memcg_oom_mutex);
mem_cgroup_oom_unlock(mem);
- /*
- * Here, we use global waitq .....more fine grained waitq ?
- * Assume following hierarchy.
- * A/
- * 01
- * 02
- * assume OOM happens both in A and 01 at the same time. Tthey are
- * mutually exclusive by lock. (kill in 01 helps A.)
- * When we use per memcg waitq, we have to wake up waiters on A and 02
- * in addtion to waiters on 01. We use global waitq for avoiding mess.
- * It will not be a big problem.
- * (And a task may be moved to other groups while it's waiting for OOM.)
- */
- wake_up_all(&memcg_oom_waitq);
+ memcg_wakeup_oom(mem);
mutex_unlock(&memcg_oom_mutex);
if (test_thread_flag(TIF_MEMDIE) || fatal_signal_pending(current))
/*
* Currently used to update mapped file statistics, but the routine can be
* generalized to update other statistics as well.
+ *
+ * Notes: Race condition
+ *
+ * We usually use page_cgroup_lock() for accessing page_cgroup member but
+ * it tends to be costly. But considering some conditions, we doesn't need
+ * to do so _always_.
+ *
+ * Considering "charge", lock_page_cgroup() is not required because all
+ * file-stat operations happen after a page is attached to radix-tree. There
+ * are no race with "charge".
+ *
+ * Considering "uncharge", we know that memcg doesn't clear pc->mem_cgroup
+ * at "uncharge" intentionally. So, we always see valid pc->mem_cgroup even
+ * if there are race with "uncharge". Statistics itself is properly handled
+ * by flags.
+ *
+ * Considering "move", this is an only case we see a race. To make the race
+ * small, we check MEM_CGROUP_ON_MOVE percpu value and detect there are
+ * possibility of race condition. If there is, we take a lock.
*/
-void mem_cgroup_update_file_mapped(struct page *page, int val)
+
+void mem_cgroup_update_page_stat(struct page *page,
+ enum mem_cgroup_page_stat_item idx, int val)
{
struct mem_cgroup *mem;
- struct page_cgroup *pc;
+ struct page_cgroup *pc = lookup_page_cgroup(page);
+ bool need_unlock = false;
+ unsigned long uninitialized_var(flags);
- pc = lookup_page_cgroup(page);
if (unlikely(!pc))
return;
- lock_page_cgroup(pc);
+ rcu_read_lock();
mem = pc->mem_cgroup;
- if (!mem || !PageCgroupUsed(pc))
- goto done;
+ if (unlikely(!mem || !PageCgroupUsed(pc)))
+ goto out;
+ /* pc->mem_cgroup is unstable ? */
+ if (unlikely(mem_cgroup_stealed(mem)) || PageTransHuge(page)) {
+ /* take a lock against to access pc->mem_cgroup */
+ move_lock_page_cgroup(pc, &flags);
+ need_unlock = true;
+ mem = pc->mem_cgroup;
+ if (!mem || !PageCgroupUsed(pc))
+ goto out;
+ }
- /*
- * Preemption is already disabled. We can use __this_cpu_xxx
- */
- if (val > 0) {
- __this_cpu_inc(mem->stat->count[MEM_CGROUP_STAT_FILE_MAPPED]);
- SetPageCgroupFileMapped(pc);
- } else {
- __this_cpu_dec(mem->stat->count[MEM_CGROUP_STAT_FILE_MAPPED]);
- ClearPageCgroupFileMapped(pc);
+ switch (idx) {
+ case MEMCG_NR_FILE_MAPPED:
+ if (val > 0)
+ SetPageCgroupFileMapped(pc);
+ else if (!page_mapped(page))
+ ClearPageCgroupFileMapped(pc);
+ idx = MEM_CGROUP_STAT_FILE_MAPPED;
+ break;
+ default:
+ BUG();
}
-done:
- unlock_page_cgroup(pc);
+ this_cpu_add(mem->stat->count[idx], val);
+
+out:
+ if (unlikely(need_unlock))
+ move_unlock_page_cgroup(pc, &flags);
+ rcu_read_unlock();
+ return;
}
+EXPORT_SYMBOL(mem_cgroup_update_page_stat);
/*
* size of first charge trial. "32" comes from vmscan.c's magic value.
atomic_dec(&memcg_drain_count);
}
-static int __cpuinit memcg_stock_cpu_callback(struct notifier_block *nb,
+/*
+ * This function drains percpu counter value from DEAD cpu and
+ * move it to local cpu. Note that this function can be preempted.
+ */
+static void mem_cgroup_drain_pcp_counter(struct mem_cgroup *mem, int cpu)
+{
+ int i;
+
+ spin_lock(&mem->pcp_counter_lock);
+ for (i = 0; i < MEM_CGROUP_STAT_DATA; i++) {
+ s64 x = per_cpu(mem->stat->count[i], cpu);
+
+ per_cpu(mem->stat->count[i], cpu) = 0;
+ mem->nocpu_base.count[i] += x;
+ }
+ /* need to clear ON_MOVE value, works as a kind of lock. */
+ per_cpu(mem->stat->count[MEM_CGROUP_ON_MOVE], cpu) = 0;
+ spin_unlock(&mem->pcp_counter_lock);
+}
+
+static void synchronize_mem_cgroup_on_move(struct mem_cgroup *mem, int cpu)
+{
+ int idx = MEM_CGROUP_ON_MOVE;
+
+ spin_lock(&mem->pcp_counter_lock);
+ per_cpu(mem->stat->count[idx], cpu) = mem->nocpu_base.count[idx];
+ spin_unlock(&mem->pcp_counter_lock);
+}
+
+static int __cpuinit memcg_cpu_hotplug_callback(struct notifier_block *nb,
unsigned long action,
void *hcpu)
{
int cpu = (unsigned long)hcpu;
struct memcg_stock_pcp *stock;
+ struct mem_cgroup *iter;
+
+ if ((action == CPU_ONLINE)) {
+ for_each_mem_cgroup_all(iter)
+ synchronize_mem_cgroup_on_move(iter, cpu);
+ return NOTIFY_OK;
+ }
- if (action != CPU_DEAD)
+ if ((action != CPU_DEAD) || action != CPU_DEAD_FROZEN)
return NOTIFY_OK;
+
+ for_each_mem_cgroup_all(iter)
+ mem_cgroup_drain_pcp_counter(iter, cpu);
+
stock = &per_cpu(memcg_stock, cpu);
drain_stock(stock);
return NOTIFY_OK;
}
+
+/* See __mem_cgroup_try_charge() for details */
+enum {
+ CHARGE_OK, /* success */
+ CHARGE_RETRY, /* need to retry but retry is not bad */
+ CHARGE_NOMEM, /* we can't do more. return -ENOMEM */
+ CHARGE_WOULDBLOCK, /* GFP_WAIT wasn't set and no enough res. */
+ CHARGE_OOM_DIE, /* the current is killed because of OOM */
+};
+
+static int __mem_cgroup_do_charge(struct mem_cgroup *mem, gfp_t gfp_mask,
+ int csize, bool oom_check)
+{
+ struct mem_cgroup *mem_over_limit;
+ struct res_counter *fail_res;
+ unsigned long flags = 0;
+ int ret;
+
+ ret = res_counter_charge(&mem->res, csize, &fail_res);
+
+ if (likely(!ret)) {
+ if (!do_swap_account)
+ return CHARGE_OK;
+ ret = res_counter_charge(&mem->memsw, csize, &fail_res);
+ if (likely(!ret))
+ return CHARGE_OK;
+
+ res_counter_uncharge(&mem->res, csize);
+ mem_over_limit = mem_cgroup_from_res_counter(fail_res, memsw);
+ flags |= MEM_CGROUP_RECLAIM_NOSWAP;
+ } else
+ mem_over_limit = mem_cgroup_from_res_counter(fail_res, res);
+ /*
+ * csize can be either a huge page (HPAGE_SIZE), a batch of
+ * regular pages (CHARGE_SIZE), or a single regular page
+ * (PAGE_SIZE).
+ *
+ * Never reclaim on behalf of optional batching, retry with a
+ * single page instead.
+ */
+ if (csize == CHARGE_SIZE)
+ return CHARGE_RETRY;
+
+ if (!(gfp_mask & __GFP_WAIT))
+ return CHARGE_WOULDBLOCK;
+
+ ret = mem_cgroup_hierarchical_reclaim(mem_over_limit, NULL,
+ gfp_mask, flags);
+ if (mem_cgroup_check_margin(mem_over_limit, csize))
+ return CHARGE_RETRY;
+ /*
+ * Even though the limit is exceeded at this point, reclaim
+ * may have been able to free some pages. Retry the charge
+ * before killing the task.
+ *
+ * Only for regular pages, though: huge pages are rather
+ * unlikely to succeed so close to the limit, and we fall back
+ * to regular pages anyway in case of failure.
+ */
+ if (csize == PAGE_SIZE && ret)
+ return CHARGE_RETRY;
+
+ /*
+ * At task move, charge accounts can be doubly counted. So, it's
+ * better to wait until the end of task_move if something is going on.
+ */
+ if (mem_cgroup_wait_acct_move(mem_over_limit))
+ return CHARGE_RETRY;
+
+ /* If we don't need to call oom-killer at el, return immediately */
+ if (!oom_check)
+ return CHARGE_NOMEM;
+ /* check OOM */
+ if (!mem_cgroup_handle_oom(mem_over_limit, gfp_mask))
+ return CHARGE_OOM_DIE;
+
+ return CHARGE_RETRY;
+}
+
/*
* Unlike exported interface, "oom" parameter is added. if oom==true,
* oom-killer can be invoked.
*/
static int __mem_cgroup_try_charge(struct mm_struct *mm,
- gfp_t gfp_mask, struct mem_cgroup **memcg, bool oom)
+ gfp_t gfp_mask,
+ struct mem_cgroup **memcg, bool oom,
+ int page_size)
{
- struct mem_cgroup *mem, *mem_over_limit;
- int nr_retries = MEM_CGROUP_RECLAIM_RETRIES;
- struct res_counter *fail_res;
- int csize = CHARGE_SIZE;
+ int nr_oom_retries = MEM_CGROUP_RECLAIM_RETRIES;
+ struct mem_cgroup *mem = NULL;
+ int ret;
+ int csize = max(CHARGE_SIZE, (unsigned long) page_size);
/*
* Unlike gloval-vm's OOM-kill, we're not in memory shortage
* thread group leader migrates. It's possible that mm is not
* set, if so charge the init_mm (happens for pagecache usage).
*/
- mem = *memcg;
- if (likely(!mem)) {
- mem = try_get_mem_cgroup_from_mm(mm);
- *memcg = mem;
- } else {
+ if (!*memcg && !mm)
+ goto bypass;
+again:
+ if (*memcg) { /* css should be a valid one */
+ mem = *memcg;
+ VM_BUG_ON(css_is_removed(&mem->css));
+ if (mem_cgroup_is_root(mem))
+ goto done;
+ if (page_size == PAGE_SIZE && consume_stock(mem))
+ goto done;
css_get(&mem->css);
- }
- if (unlikely(!mem))
- return 0;
-
- VM_BUG_ON(css_is_removed(&mem->css));
- if (mem_cgroup_is_root(mem))
- goto done;
-
- while (1) {
- int ret = 0;
- unsigned long flags = 0;
+ } else {
+ struct task_struct *p;
- if (consume_stock(mem))
+ rcu_read_lock();
+ p = rcu_dereference(mm->owner);
+ /*
+ * Because we don't have task_lock(), "p" can exit.
+ * In that case, "mem" can point to root or p can be NULL with
+ * race with swapoff. Then, we have small risk of mis-accouning.
+ * But such kind of mis-account by race always happens because
+ * we don't have cgroup_mutex(). It's overkill and we allo that
+ * small race, here.
+ * (*) swapoff at el will charge against mm-struct not against
+ * task-struct. So, mm->owner can be NULL.
+ */
+ mem = mem_cgroup_from_task(p);
+ if (!mem || mem_cgroup_is_root(mem)) {
+ rcu_read_unlock();
goto done;
-
- ret = res_counter_charge(&mem->res, csize, &fail_res);
- if (likely(!ret)) {
- if (!do_swap_account)
- break;
- ret = res_counter_charge(&mem->memsw, csize, &fail_res);
- if (likely(!ret))
- break;
- /* mem+swap counter fails */
- res_counter_uncharge(&mem->res, csize);
- flags |= MEM_CGROUP_RECLAIM_NOSWAP;
- mem_over_limit = mem_cgroup_from_res_counter(fail_res,
- memsw);
- } else
- /* mem counter fails */
- mem_over_limit = mem_cgroup_from_res_counter(fail_res,
- res);
-
- /* reduce request size and retry */
- if (csize > PAGE_SIZE) {
- csize = PAGE_SIZE;
- continue;
}
- if (!(gfp_mask & __GFP_WAIT))
- goto nomem;
+ if (page_size == PAGE_SIZE && consume_stock(mem)) {
+ /*
+ * It seems dagerous to access memcg without css_get().
+ * But considering how consume_stok works, it's not
+ * necessary. If consume_stock success, some charges
+ * from this memcg are cached on this cpu. So, we
+ * don't need to call css_get()/css_tryget() before
+ * calling consume_stock().
+ */
+ rcu_read_unlock();
+ goto done;
+ }
+ /* after here, we may be blocked. we need to get refcnt */
+ if (!css_tryget(&mem->css)) {
+ rcu_read_unlock();
+ goto again;
+ }
+ rcu_read_unlock();
+ }
- ret = mem_cgroup_hierarchical_reclaim(mem_over_limit, NULL,
- gfp_mask, flags);
- if (ret)
- continue;
+ do {
+ bool oom_check;
- /*
- * try_to_free_mem_cgroup_pages() might not give us a full
- * picture of reclaim. Some pages are reclaimed and might be
- * moved to swap cache or just unmapped from the cgroup.
- * Check the limit again to see if the reclaim reduced the
- * current usage of the cgroup before giving up
- *
- */
- if (mem_cgroup_check_under_limit(mem_over_limit))
- continue;
+ /* If killed, bypass charge */
+ if (fatal_signal_pending(current)) {
+ css_put(&mem->css);
+ goto bypass;
+ }
- /* try to avoid oom while someone is moving charge */
- if (mc.moving_task && current != mc.moving_task) {
- struct mem_cgroup *from, *to;
- bool do_continue = false;
- /*
- * There is a small race that "from" or "to" can be
- * freed by rmdir, so we use css_tryget().
- */
- from = mc.from;
- to = mc.to;
- if (from && css_tryget(&from->css)) {
- if (mem_over_limit->use_hierarchy)
- do_continue = css_is_ancestor(
- &from->css,
- &mem_over_limit->css);
- else
- do_continue = (from == mem_over_limit);
- css_put(&from->css);
- }
- if (!do_continue && to && css_tryget(&to->css)) {
- if (mem_over_limit->use_hierarchy)
- do_continue = css_is_ancestor(
- &to->css,
- &mem_over_limit->css);
- else
- do_continue = (to == mem_over_limit);
- css_put(&to->css);
- }
- if (do_continue) {
- DEFINE_WAIT(wait);
- prepare_to_wait(&mc.waitq, &wait,
- TASK_INTERRUPTIBLE);
- /* moving charge context might have finished. */
- if (mc.moving_task)
- schedule();
- finish_wait(&mc.waitq, &wait);
- continue;
- }
+ oom_check = false;
+ if (oom && !nr_oom_retries) {
+ oom_check = true;
+ nr_oom_retries = MEM_CGROUP_RECLAIM_RETRIES;
}
- if (!nr_retries--) {
- if (!oom)
+ ret = __mem_cgroup_do_charge(mem, gfp_mask, csize, oom_check);
+
+ switch (ret) {
+ case CHARGE_OK:
+ break;
+ case CHARGE_RETRY: /* not in OOM situation but retry */
+ csize = page_size;
+ css_put(&mem->css);
+ mem = NULL;
+ goto again;
+ case CHARGE_WOULDBLOCK: /* !__GFP_WAIT */
+ css_put(&mem->css);
+ goto nomem;
+ case CHARGE_NOMEM: /* OOM routine works */
+ if (!oom) {
+ css_put(&mem->css);
goto nomem;
- if (mem_cgroup_handle_oom(mem_over_limit, gfp_mask)) {
- nr_retries = MEM_CGROUP_RECLAIM_RETRIES;
- continue;
}
- /* When we reach here, current task is dying .*/
+ /* If oom, we never return -ENOMEM */
+ nr_oom_retries--;
+ break;
+ case CHARGE_OOM_DIE: /* Killed by OOM Killer */
css_put(&mem->css);
goto bypass;
}
- }
- if (csize > PAGE_SIZE)
- refill_stock(mem, csize - PAGE_SIZE);
+ } while (ret != CHARGE_OK);
+
+ if (csize > page_size)
+ refill_stock(mem, csize - page_size);
+ css_put(&mem->css);
done:
+ *memcg = mem;
return 0;
nomem:
- css_put(&mem->css);
+ *memcg = NULL;
return -ENOMEM;
bypass:
*memcg = NULL;
res_counter_uncharge(&mem->res, PAGE_SIZE * count);
if (do_swap_account)
res_counter_uncharge(&mem->memsw, PAGE_SIZE * count);
- VM_BUG_ON(test_bit(CSS_ROOT, &mem->css.flags));
- WARN_ON_ONCE(count > INT_MAX);
- __css_put(&mem->css, (int)count);
}
- /* we don't need css_put for root */
}
-static void mem_cgroup_cancel_charge(struct mem_cgroup *mem)
+static void mem_cgroup_cancel_charge(struct mem_cgroup *mem,
+ int page_size)
{
- __mem_cgroup_cancel_charge(mem, 1);
+ __mem_cgroup_cancel_charge(mem, page_size >> PAGE_SHIFT);
}
/*
return mem;
}
-/*
- * commit a charge got by __mem_cgroup_try_charge() and makes page_cgroup to be
- * USED state. If already USED, uncharge and return.
- */
-
static void __mem_cgroup_commit_charge(struct mem_cgroup *mem,
- struct page_cgroup *pc,
- enum charge_type ctype)
+ struct page_cgroup *pc,
+ enum charge_type ctype,
+ int page_size)
{
+ int nr_pages = page_size >> PAGE_SHIFT;
+
/* try_charge() can return NULL to *memcg, taking care of it. */
if (!mem)
return;
lock_page_cgroup(pc);
if (unlikely(PageCgroupUsed(pc))) {
unlock_page_cgroup(pc);
- mem_cgroup_cancel_charge(mem);
+ mem_cgroup_cancel_charge(mem, page_size);
return;
}
-
+ /*
+ * we don't need page_cgroup_lock about tail pages, becase they are not
+ * accessed by any other context at this point.
+ */
pc->mem_cgroup = mem;
/*
* We access a page_cgroup asynchronously without lock_page_cgroup().
break;
}
- mem_cgroup_charge_statistics(mem, pc, true);
-
+ mem_cgroup_charge_statistics(mem, PageCgroupCache(pc), nr_pages);
unlock_page_cgroup(pc);
/*
* "charge_statistics" updated event counter. Then, check it.
memcg_check_events(mem, pc->page);
}
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+
+#define PCGF_NOCOPY_AT_SPLIT ((1 << PCG_LOCK) | (1 << PCG_MOVE_LOCK) |\
+ (1 << PCG_ACCT_LRU) | (1 << PCG_MIGRATION))
+/*
+ * Because tail pages are not marked as "used", set it. We're under
+ * zone->lru_lock, 'splitting on pmd' and compund_lock.
+ */
+void mem_cgroup_split_huge_fixup(struct page *head, struct page *tail)
+{
+ struct page_cgroup *head_pc = lookup_page_cgroup(head);
+ struct page_cgroup *tail_pc = lookup_page_cgroup(tail);
+ unsigned long flags;
+
+ if (mem_cgroup_disabled())
+ return;
+ /*
+ * We have no races with charge/uncharge but will have races with
+ * page state accounting.
+ */
+ move_lock_page_cgroup(head_pc, &flags);
+
+ tail_pc->mem_cgroup = head_pc->mem_cgroup;
+ smp_wmb(); /* see __commit_charge() */
+ if (PageCgroupAcctLRU(head_pc)) {
+ enum lru_list lru;
+ struct mem_cgroup_per_zone *mz;
+
+ /*
+ * LRU flags cannot be copied because we need to add tail
+ *.page to LRU by generic call and our hook will be called.
+ * We hold lru_lock, then, reduce counter directly.
+ */
+ lru = page_lru(head);
+ mz = page_cgroup_zoneinfo(head_pc);
+ MEM_CGROUP_ZSTAT(mz, lru) -= 1;
+ }
+ tail_pc->flags = head_pc->flags & ~PCGF_NOCOPY_AT_SPLIT;
+ move_unlock_page_cgroup(head_pc, &flags);
+}
+#endif
+
/**
* __mem_cgroup_move_account - move account of the page
* @pc: page_cgroup of the page.
*/
static void __mem_cgroup_move_account(struct page_cgroup *pc,
- struct mem_cgroup *from, struct mem_cgroup *to, bool uncharge)
+ struct mem_cgroup *from, struct mem_cgroup *to, bool uncharge,
+ int charge_size)
{
+ int nr_pages = charge_size >> PAGE_SHIFT;
+
VM_BUG_ON(from == to);
VM_BUG_ON(PageLRU(pc->page));
- VM_BUG_ON(!PageCgroupLocked(pc));
+ VM_BUG_ON(!page_is_cgroup_locked(pc));
VM_BUG_ON(!PageCgroupUsed(pc));
VM_BUG_ON(pc->mem_cgroup != from);
__this_cpu_inc(to->stat->count[MEM_CGROUP_STAT_FILE_MAPPED]);
preempt_enable();
}
- mem_cgroup_charge_statistics(from, pc, false);
+ mem_cgroup_charge_statistics(from, PageCgroupCache(pc), -nr_pages);
if (uncharge)
/* This is not "cancel", but cancel_charge does all we need. */
- mem_cgroup_cancel_charge(from);
+ mem_cgroup_cancel_charge(from, charge_size);
/* caller should have done css_get */
pc->mem_cgroup = to;
- mem_cgroup_charge_statistics(to, pc, true);
+ mem_cgroup_charge_statistics(to, PageCgroupCache(pc), nr_pages);
/*
* We charges against "to" which may not have any tasks. Then, "to"
* can be under rmdir(). But in current implementation, caller of
* __mem_cgroup_move_account()
*/
static int mem_cgroup_move_account(struct page_cgroup *pc,
- struct mem_cgroup *from, struct mem_cgroup *to, bool uncharge)
+ struct mem_cgroup *from, struct mem_cgroup *to,
+ bool uncharge, int charge_size)
{
int ret = -EINVAL;
+ unsigned long flags;
+ /*
+ * The page is isolated from LRU. So, collapse function
+ * will not handle this page. But page splitting can happen.
+ * Do this check under compound_page_lock(). The caller should
+ * hold it.
+ */
+ if ((charge_size > PAGE_SIZE) && !PageTransHuge(pc->page))
+ return -EBUSY;
+
lock_page_cgroup(pc);
if (PageCgroupUsed(pc) && pc->mem_cgroup == from) {
- __mem_cgroup_move_account(pc, from, to, uncharge);
+ move_lock_page_cgroup(pc, &flags);
+ __mem_cgroup_move_account(pc, from, to, uncharge, charge_size);
+ move_unlock_page_cgroup(pc, &flags);
ret = 0;
}
unlock_page_cgroup(pc);
struct cgroup *cg = child->css.cgroup;
struct cgroup *pcg = cg->parent;
struct mem_cgroup *parent;
+ int page_size = PAGE_SIZE;
+ unsigned long flags;
int ret;
/* Is ROOT ? */
if (isolate_lru_page(page))
goto put;
+ if (PageTransHuge(page))
+ page_size = HPAGE_SIZE;
+
parent = mem_cgroup_from_cont(pcg);
- ret = __mem_cgroup_try_charge(NULL, gfp_mask, &parent, false);
+ ret = __mem_cgroup_try_charge(NULL, gfp_mask,
+ &parent, false, page_size);
if (ret || !parent)
goto put_back;
- ret = mem_cgroup_move_account(pc, child, parent, true);
+ if (page_size > PAGE_SIZE)
+ flags = compound_lock_irqsave(page);
+
+ ret = mem_cgroup_move_account(pc, child, parent, true, page_size);
if (ret)
- mem_cgroup_cancel_charge(parent);
+ mem_cgroup_cancel_charge(parent, page_size);
+
+ if (page_size > PAGE_SIZE)
+ compound_unlock_irqrestore(page, flags);
put_back:
putback_lru_page(page);
put:
* < 0 if the cgroup is over its limit
*/
static int mem_cgroup_charge_common(struct page *page, struct mm_struct *mm,
- gfp_t gfp_mask, enum charge_type ctype,
- struct mem_cgroup *memcg)
+ gfp_t gfp_mask, enum charge_type ctype)
{
- struct mem_cgroup *mem;
+ struct mem_cgroup *mem = NULL;
+ int page_size = PAGE_SIZE;
struct page_cgroup *pc;
+ bool oom = true;
int ret;
+ if (PageTransHuge(page)) {
+ page_size <<= compound_order(page);
+ VM_BUG_ON(!PageTransHuge(page));
+ /*
+ * Never OOM-kill a process for a huge page. The
+ * fault handler will fall back to regular pages.
+ */
+ oom = false;
+ }
+
pc = lookup_page_cgroup(page);
/* can happen at boot */
if (unlikely(!pc))
return 0;
prefetchw(pc);
- mem = memcg;
- ret = __mem_cgroup_try_charge(mm, gfp_mask, &mem, true);
+ ret = __mem_cgroup_try_charge(mm, gfp_mask, &mem, oom, page_size);
if (ret || !mem)
return ret;
- __mem_cgroup_commit_charge(mem, pc, ctype);
+ __mem_cgroup_commit_charge(mem, pc, ctype, page_size);
return 0;
}
{
if (mem_cgroup_disabled())
return 0;
- if (PageCompound(page))
- return 0;
/*
* If already mapped, we don't have to account.
* If page cache, page->mapping has address_space.
if (unlikely(!mm))
mm = &init_mm;
return mem_cgroup_charge_common(page, mm, gfp_mask,
- MEM_CGROUP_CHARGE_TYPE_MAPPED, NULL);
+ MEM_CGROUP_CHARGE_TYPE_MAPPED);
}
static void
int mem_cgroup_cache_charge(struct page *page, struct mm_struct *mm,
gfp_t gfp_mask)
{
- struct mem_cgroup *mem = NULL;
int ret;
if (mem_cgroup_disabled())
if (!(gfp_mask & __GFP_WAIT)) {
struct page_cgroup *pc;
-
pc = lookup_page_cgroup(page);
if (!pc)
return 0;
unlock_page_cgroup(pc);
}
- if (unlikely(!mm && !mem))
+ if (unlikely(!mm))
mm = &init_mm;
if (page_is_file_cache(page))
return mem_cgroup_charge_common(page, mm, gfp_mask,
- MEM_CGROUP_CHARGE_TYPE_CACHE, NULL);
+ MEM_CGROUP_CHARGE_TYPE_CACHE);
/* shmem */
if (PageSwapCache(page)) {
+ struct mem_cgroup *mem = NULL;
+
ret = mem_cgroup_try_charge_swapin(mm, page, gfp_mask, &mem);
if (!ret)
__mem_cgroup_commit_charge_swapin(page, mem,
MEM_CGROUP_CHARGE_TYPE_SHMEM);
} else
ret = mem_cgroup_charge_common(page, mm, gfp_mask,
- MEM_CGROUP_CHARGE_TYPE_SHMEM, mem);
+ MEM_CGROUP_CHARGE_TYPE_SHMEM);
return ret;
}
if (!mem)
goto charge_cur_mm;
*ptr = mem;
- ret = __mem_cgroup_try_charge(NULL, mask, ptr, true);
- /* drop extra refcnt from tryget */
+ ret = __mem_cgroup_try_charge(NULL, mask, ptr, true, PAGE_SIZE);
css_put(&mem->css);
return ret;
charge_cur_mm:
if (unlikely(!mm))
mm = &init_mm;
- return __mem_cgroup_try_charge(mm, mask, ptr, true);
+ return __mem_cgroup_try_charge(mm, mask, ptr, true, PAGE_SIZE);
}
static void
cgroup_exclude_rmdir(&ptr->css);
pc = lookup_page_cgroup(page);
mem_cgroup_lru_del_before_commit_swapcache(page);
- __mem_cgroup_commit_charge(ptr, pc, ctype);
+ __mem_cgroup_commit_charge(ptr, pc, ctype, PAGE_SIZE);
mem_cgroup_lru_add_after_commit_swapcache(page);
/*
* Now swap is on-memory. This means this page may be
return;
if (!mem)
return;
- mem_cgroup_cancel_charge(mem);
+ mem_cgroup_cancel_charge(mem, PAGE_SIZE);
}
static void
-__do_uncharge(struct mem_cgroup *mem, const enum charge_type ctype)
+__do_uncharge(struct mem_cgroup *mem, const enum charge_type ctype,
+ int page_size)
{
struct memcg_batch_info *batch = NULL;
bool uncharge_memsw = true;
/* If swapout, usage of swap doesn't decrease */
if (!do_swap_account || ctype == MEM_CGROUP_CHARGE_TYPE_SWAPOUT)
uncharge_memsw = false;
- /*
- * do_batch > 0 when unmapping pages or inode invalidate/truncate.
- * In those cases, all pages freed continously can be expected to be in
- * the same cgroup and we have chance to coalesce uncharges.
- * But we do uncharge one by one if this is killed by OOM(TIF_MEMDIE)
- * because we want to do uncharge as soon as possible.
- */
- if (!current->memcg_batch.do_batch || test_thread_flag(TIF_MEMDIE))
- goto direct_uncharge;
batch = ¤t->memcg_batch;
/*
if (!batch->memcg)
batch->memcg = mem;
/*
+ * do_batch > 0 when unmapping pages or inode invalidate/truncate.
+ * In those cases, all pages freed continously can be expected to be in
+ * the same cgroup and we have chance to coalesce uncharges.
+ * But we do uncharge one by one if this is killed by OOM(TIF_MEMDIE)
+ * because we want to do uncharge as soon as possible.
+ */
+
+ if (!batch->do_batch || test_thread_flag(TIF_MEMDIE))
+ goto direct_uncharge;
+
+ if (page_size != PAGE_SIZE)
+ goto direct_uncharge;
+
+ /*
* In typical case, batch->memcg == mem. This means we can
* merge a series of uncharges to an uncharge of res_counter.
* If not, we uncharge res_counter ony by one.
batch->memsw_bytes += PAGE_SIZE;
return;
direct_uncharge:
- res_counter_uncharge(&mem->res, PAGE_SIZE);
+ res_counter_uncharge(&mem->res, page_size);
if (uncharge_memsw)
- res_counter_uncharge(&mem->memsw, PAGE_SIZE);
+ res_counter_uncharge(&mem->memsw, page_size);
+ if (unlikely(batch->memcg != mem))
+ memcg_oom_recover(mem);
return;
}
static struct mem_cgroup *
__mem_cgroup_uncharge_common(struct page *page, enum charge_type ctype)
{
+ int count;
struct page_cgroup *pc;
struct mem_cgroup *mem = NULL;
- struct mem_cgroup_per_zone *mz;
+ int page_size = PAGE_SIZE;
if (mem_cgroup_disabled())
return NULL;
if (PageSwapCache(page))
return NULL;
+ if (PageTransHuge(page)) {
+ page_size <<= compound_order(page);
+ VM_BUG_ON(!PageTransHuge(page));
+ }
+
+ count = page_size >> PAGE_SHIFT;
/*
* Check if our page_cgroup is valid
*/
switch (ctype) {
case MEM_CGROUP_CHARGE_TYPE_MAPPED:
case MEM_CGROUP_CHARGE_TYPE_DROP:
- if (page_mapped(page))
+ /* See mem_cgroup_prepare_migration() */
+ if (page_mapped(page) || PageCgroupMigration(pc))
goto unlock_out;
break;
case MEM_CGROUP_CHARGE_TYPE_SWAPOUT:
break;
}
- if (!mem_cgroup_is_root(mem))
- __do_uncharge(mem, ctype);
- if (ctype == MEM_CGROUP_CHARGE_TYPE_SWAPOUT)
- mem_cgroup_swap_statistics(mem, true);
- mem_cgroup_charge_statistics(mem, pc, false);
+ mem_cgroup_charge_statistics(mem, PageCgroupCache(pc), -count);
ClearPageCgroupUsed(pc);
/*
* special functions.
*/
- mz = page_cgroup_zoneinfo(pc);
unlock_page_cgroup(pc);
-
+ /*
+ * even after unlock, we have mem->res.usage here and this memcg
+ * will never be freed.
+ */
memcg_check_events(mem, page);
- /* at swapout, this memcg will be accessed to record to swap */
- if (ctype != MEM_CGROUP_CHARGE_TYPE_SWAPOUT)
- css_put(&mem->css);
+ if (do_swap_account && ctype == MEM_CGROUP_CHARGE_TYPE_SWAPOUT) {
+ mem_cgroup_swap_statistics(mem, true);
+ mem_cgroup_get(mem);
+ }
+ if (!mem_cgroup_is_root(mem))
+ __do_uncharge(mem, ctype, page_size);
return mem;
res_counter_uncharge(&batch->memcg->res, batch->bytes);
if (batch->memsw_bytes)
res_counter_uncharge(&batch->memcg->memsw, batch->memsw_bytes);
+ memcg_oom_recover(batch->memcg);
/* forget this pointer (for sanity check) */
batch->memcg = NULL;
}
memcg = __mem_cgroup_uncharge_common(page, ctype);
- /* record memcg information */
- if (do_swap_account && swapout && memcg) {
+ /*
+ * record memcg information, if swapout && memcg != NULL,
+ * mem_cgroup_get() was called in uncharge().
+ */
+ if (do_swap_account && swapout && memcg)
swap_cgroup_record(ent, css_id(&memcg->css));
- mem_cgroup_get(memcg);
- }
- if (swapout && memcg)
- css_put(&memcg->css);
}
#endif
*/
if (!mem_cgroup_is_root(to))
res_counter_uncharge(&to->res, PAGE_SIZE);
- css_put(&to->css);
}
return 0;
}
* Before starting migration, account PAGE_SIZE to mem_cgroup that the old
* page belongs to.
*/
-int mem_cgroup_prepare_migration(struct page *page, struct mem_cgroup **ptr)
+int mem_cgroup_prepare_migration(struct page *page,
+ struct page *newpage, struct mem_cgroup **ptr)
{
struct page_cgroup *pc;
struct mem_cgroup *mem = NULL;
+ enum charge_type ctype;
int ret = 0;
+ VM_BUG_ON(PageTransHuge(page));
if (mem_cgroup_disabled())
return 0;
if (PageCgroupUsed(pc)) {
mem = pc->mem_cgroup;
css_get(&mem->css);
+ /*
+ * At migrating an anonymous page, its mapcount goes down
+ * to 0 and uncharge() will be called. But, even if it's fully
+ * unmapped, migration may fail and this page has to be
+ * charged again. We set MIGRATION flag here and delay uncharge
+ * until end_migration() is called
+ *
+ * Corner Case Thinking
+ * A)
+ * When the old page was mapped as Anon and it's unmap-and-freed
+ * while migration was ongoing.
+ * If unmap finds the old page, uncharge() of it will be delayed
+ * until end_migration(). If unmap finds a new page, it's
+ * uncharged when it make mapcount to be 1->0. If unmap code
+ * finds swap_migration_entry, the new page will not be mapped
+ * and end_migration() will find it(mapcount==0).
+ *
+ * B)
+ * When the old page was mapped but migraion fails, the kernel
+ * remaps it. A charge for it is kept by MIGRATION flag even
+ * if mapcount goes down to 0. We can do remap successfully
+ * without charging it again.
+ *
+ * C)
+ * The "old" page is under lock_page() until the end of
+ * migration, so, the old page itself will not be swapped-out.
+ * If the new page is swapped out before end_migraton, our
+ * hook to usual swap-out path will catch the event.
+ */
+ if (PageAnon(page))
+ SetPageCgroupMigration(pc);
}
unlock_page_cgroup(pc);
+ /*
+ * If the page is not charged at this point,
+ * we return here.
+ */
+ if (!mem)
+ return 0;
*ptr = mem;
- if (mem) {
- ret = __mem_cgroup_try_charge(NULL, GFP_KERNEL, ptr, false);
- css_put(&mem->css);
+ ret = __mem_cgroup_try_charge(NULL, GFP_KERNEL, ptr, false, PAGE_SIZE);
+ css_put(&mem->css);/* drop extra refcnt */
+ if (ret || *ptr == NULL) {
+ if (PageAnon(page)) {
+ lock_page_cgroup(pc);
+ ClearPageCgroupMigration(pc);
+ unlock_page_cgroup(pc);
+ /*
+ * The old page may be fully unmapped while we kept it.
+ */
+ mem_cgroup_uncharge_page(page);
+ }
+ return -ENOMEM;
}
+ /*
+ * We charge new page before it's used/mapped. So, even if unlock_page()
+ * is called before end_migration, we can catch all events on this new
+ * page. In the case new page is migrated but not remapped, new page's
+ * mapcount will be finally 0 and we call uncharge in end_migration().
+ */
+ pc = lookup_page_cgroup(newpage);
+ if (PageAnon(page))
+ ctype = MEM_CGROUP_CHARGE_TYPE_MAPPED;
+ else if (page_is_file_cache(page))
+ ctype = MEM_CGROUP_CHARGE_TYPE_CACHE;
+ else
+ ctype = MEM_CGROUP_CHARGE_TYPE_SHMEM;
+ __mem_cgroup_commit_charge(mem, pc, ctype, PAGE_SIZE);
return ret;
}
/* remove redundant charge if migration failed*/
void mem_cgroup_end_migration(struct mem_cgroup *mem,
- struct page *oldpage, struct page *newpage)
+ struct page *oldpage, struct page *newpage, bool migration_ok)
{
- struct page *target, *unused;
+ struct page *used, *unused;
struct page_cgroup *pc;
- enum charge_type ctype;
if (!mem)
return;
+ /* blocks rmdir() */
cgroup_exclude_rmdir(&mem->css);
- /* at migration success, oldpage->mapping is NULL. */
- if (oldpage->mapping) {
- target = oldpage;
- unused = NULL;
+ if (!migration_ok) {
+ used = oldpage;
+ unused = newpage;
} else {
- target = newpage;
+ used = newpage;
unused = oldpage;
}
-
- if (PageAnon(target))
- ctype = MEM_CGROUP_CHARGE_TYPE_MAPPED;
- else if (page_is_file_cache(target))
- ctype = MEM_CGROUP_CHARGE_TYPE_CACHE;
- else
- ctype = MEM_CGROUP_CHARGE_TYPE_SHMEM;
-
- /* unused page is not on radix-tree now. */
- if (unused)
- __mem_cgroup_uncharge_common(unused, ctype);
-
- pc = lookup_page_cgroup(target);
/*
- * __mem_cgroup_commit_charge() check PCG_USED bit of page_cgroup.
- * So, double-counting is effectively avoided.
+ * We disallowed uncharge of pages under migration because mapcount
+ * of the page goes down to zero, temporarly.
+ * Clear the flag and check the page should be charged.
*/
- __mem_cgroup_commit_charge(mem, pc, ctype);
+ pc = lookup_page_cgroup(oldpage);
+ lock_page_cgroup(pc);
+ ClearPageCgroupMigration(pc);
+ unlock_page_cgroup(pc);
+
+ __mem_cgroup_uncharge_common(unused, MEM_CGROUP_CHARGE_TYPE_FORCE);
/*
- * Both of oldpage and newpage are still under lock_page().
- * Then, we don't have to care about race in radix-tree.
- * But we have to be careful that this page is unmapped or not.
- *
- * There is a case for !page_mapped(). At the start of
- * migration, oldpage was mapped. But now, it's zapped.
- * But we know *target* page is not freed/reused under us.
- * mem_cgroup_uncharge_page() does all necessary checks.
+ * If a page is a file cache, radix-tree replacement is very atomic
+ * and we can skip this check. When it was an Anon page, its mapcount
+ * goes down to 0. But because we added MIGRATION flage, it's not
+ * uncharged yet. There are several case but page->mapcount check
+ * and USED bit check in mem_cgroup_uncharge_page() will do enough
+ * check. (see prepare_charge() also)
*/
- if (ctype == MEM_CGROUP_CHARGE_TYPE_MAPPED)
- mem_cgroup_uncharge_page(target);
+ if (PageAnon(used))
+ mem_cgroup_uncharge_page(used);
/*
- * At migration, we may charge account against cgroup which has no tasks
+ * At migration, we may charge account against cgroup which has no
+ * tasks.
* So, rmdir()->pre_destroy() can be called while we do this charge.
* In that case, we need to call pre_destroy() again. check it here.
*/
unsigned long long val)
{
int retry_count;
- u64 memswlimit;
+ u64 memswlimit, memlimit;
int ret = 0;
int children = mem_cgroup_count_children(memcg);
u64 curusage, oldusage;
+ int enlarge;
/*
* For keeping hierarchical_reclaim simple, how long we should retry
oldusage = res_counter_read_u64(&memcg->res, RES_USAGE);
+ enlarge = 0;
while (retry_count) {
if (signal_pending(current)) {
ret = -EINTR;
mutex_unlock(&set_limit_mutex);
break;
}
+
+ memlimit = res_counter_read_u64(&memcg->res, RES_LIMIT);
+ if (memlimit < val)
+ enlarge = 1;
+
ret = res_counter_set_limit(&memcg->res, val);
if (!ret) {
if (memswlimit == val)
else
oldusage = curusage;
}
+ if (!ret && enlarge)
+ memcg_oom_recover(memcg);
return ret;
}
unsigned long long val)
{
int retry_count;
- u64 memlimit, oldusage, curusage;
+ u64 memlimit, memswlimit, oldusage, curusage;
int children = mem_cgroup_count_children(memcg);
int ret = -EBUSY;
+ int enlarge = 0;
/* see mem_cgroup_resize_res_limit */
retry_count = children * MEM_CGROUP_RECLAIM_RETRIES;
mutex_unlock(&set_limit_mutex);
break;
}
+ memswlimit = res_counter_read_u64(&memcg->memsw, RES_LIMIT);
+ if (memswlimit < val)
+ enlarge = 1;
ret = res_counter_set_limit(&memcg->memsw, val);
if (!ret) {
if (memlimit == val)
else
oldusage = curusage;
}
+ if (!ret && enlarge)
+ memcg_oom_recover(memcg);
return ret;
}
unsigned long mem_cgroup_soft_limit_reclaim(struct zone *zone, int order,
- gfp_t gfp_mask, int nid,
- int zid)
+ gfp_t gfp_mask)
{
unsigned long nr_reclaimed = 0;
struct mem_cgroup_per_zone *mz, *next_mz = NULL;
if (order > 0)
return 0;
- mctz = soft_limit_tree_node_zone(nid, zid);
+ mctz = soft_limit_tree_node_zone(zone_to_nid(zone), zone_idx(zone));
/*
* This loop can run a while, specially if mem_cgroup's continuously
* keep exceeding their soft limit and putting the system under
lru_add_drain_all();
drain_all_stock_sync();
ret = 0;
+ mem_cgroup_start_move(mem);
for_each_node_state(node, N_HIGH_MEMORY) {
for (zid = 0; !ret && zid < MAX_NR_ZONES; zid++) {
enum lru_list l;
if (ret)
break;
}
+ mem_cgroup_end_move(mem);
+ memcg_oom_recover(mem);
/* it seems parent cgroup doesn't have enough mem */
if (ret == -ENOMEM)
goto try_to_free;
return retval;
}
-struct mem_cgroup_idx_data {
- s64 val;
- enum mem_cgroup_stat_index idx;
-};
-static int
-mem_cgroup_get_idx_stat(struct mem_cgroup *mem, void *data)
+static u64 mem_cgroup_get_recursive_idx_stat(struct mem_cgroup *mem,
+ enum mem_cgroup_stat_index idx)
{
- struct mem_cgroup_idx_data *d = data;
- d->val += mem_cgroup_read_stat(mem, d->idx);
- return 0;
-}
+ struct mem_cgroup *iter;
+ s64 val = 0;
-static void
-mem_cgroup_get_recursive_idx_stat(struct mem_cgroup *mem,
- enum mem_cgroup_stat_index idx, s64 *val)
-{
- struct mem_cgroup_idx_data d;
- d.idx = idx;
- d.val = 0;
- mem_cgroup_walk_tree(mem, &d, mem_cgroup_get_idx_stat);
- *val = d.val;
+ /* each per cpu's value can be minus.Then, use s64 */
+ for_each_mem_cgroup_tree(iter, mem)
+ val += mem_cgroup_read_stat(iter, idx);
+
+ if (val < 0) /* race ? */
+ val = 0;
+ return val;
}
static inline u64 mem_cgroup_usage(struct mem_cgroup *mem, bool swap)
{
- u64 idx_val, val;
+ u64 val;
if (!mem_cgroup_is_root(mem)) {
if (!swap)
return res_counter_read_u64(&mem->memsw, RES_USAGE);
}
- mem_cgroup_get_recursive_idx_stat(mem, MEM_CGROUP_STAT_CACHE, &idx_val);
- val = idx_val;
- mem_cgroup_get_recursive_idx_stat(mem, MEM_CGROUP_STAT_RSS, &idx_val);
- val += idx_val;
+ val = mem_cgroup_get_recursive_idx_stat(mem, MEM_CGROUP_STAT_CACHE);
+ val += mem_cgroup_get_recursive_idx_stat(mem, MEM_CGROUP_STAT_RSS);
- if (swap) {
- mem_cgroup_get_recursive_idx_stat(mem,
- MEM_CGROUP_STAT_SWAPOUT, &idx_val);
- val += idx_val;
- }
+ if (swap)
+ val += mem_cgroup_get_recursive_idx_stat(mem,
+ MEM_CGROUP_STAT_SWAPOUT);
return val << PAGE_SHIFT;
}
};
-static int mem_cgroup_get_local_stat(struct mem_cgroup *mem, void *data)
+static void
+mem_cgroup_get_local_stat(struct mem_cgroup *mem, struct mcs_total_stat *s)
{
- struct mcs_total_stat *s = data;
s64 val;
/* per cpu stat */
s->stat[MCS_ACTIVE_FILE] += val * PAGE_SIZE;
val = mem_cgroup_get_local_zonestat(mem, LRU_UNEVICTABLE);
s->stat[MCS_UNEVICTABLE] += val * PAGE_SIZE;
- return 0;
}
static void
mem_cgroup_get_total_stat(struct mem_cgroup *mem, struct mcs_total_stat *s)
{
- mem_cgroup_walk_tree(mem, s, mem_cgroup_get_local_stat);
+ struct mem_cgroup *iter;
+
+ for_each_mem_cgroup_tree(iter, mem)
+ mem_cgroup_get_local_stat(iter, s);
}
static int mem_control_stat_show(struct cgroup *cont, struct cftype *cft,
rcu_read_lock();
if (!swap)
- t = rcu_dereference(memcg->thresholds);
+ t = rcu_dereference(memcg->thresholds.primary);
else
- t = rcu_dereference(memcg->memsw_thresholds);
+ t = rcu_dereference(memcg->memsw_thresholds.primary);
if (!t)
goto unlock;
* If it's not true, a threshold was crossed after last
* call of __mem_cgroup_threshold().
*/
- i = atomic_read(&t->current_threshold);
+ i = t->current_threshold;
/*
* Iterate backward over array of thresholds starting from
eventfd_signal(t->entries[i].eventfd, 1);
/* Update current_threshold */
- atomic_set(&t->current_threshold, i - 1);
+ t->current_threshold = i - 1;
unlock:
rcu_read_unlock();
}
static void mem_cgroup_threshold(struct mem_cgroup *memcg)
{
- __mem_cgroup_threshold(memcg, false);
- if (do_swap_account)
- __mem_cgroup_threshold(memcg, true);
+ while (memcg) {
+ __mem_cgroup_threshold(memcg, false);
+ if (do_swap_account)
+ __mem_cgroup_threshold(memcg, true);
+
+ memcg = parent_mem_cgroup(memcg);
+ }
}
static int compare_thresholds(const void *a, const void *b)
return _a->threshold - _b->threshold;
}
-static int mem_cgroup_register_event(struct cgroup *cgrp, struct cftype *cft,
- struct eventfd_ctx *eventfd, const char *args)
+static int mem_cgroup_oom_notify_cb(struct mem_cgroup *mem)
+{
+ struct mem_cgroup_eventfd_list *ev;
+
+ list_for_each_entry(ev, &mem->oom_notify, list)
+ eventfd_signal(ev->eventfd, 1);
+ return 0;
+}
+
+static void mem_cgroup_oom_notify(struct mem_cgroup *mem)
+{
+ struct mem_cgroup *iter;
+
+ for_each_mem_cgroup_tree(iter, mem)
+ mem_cgroup_oom_notify_cb(iter);
+}
+
+static int mem_cgroup_usage_register_event(struct cgroup *cgrp,
+ struct cftype *cft, struct eventfd_ctx *eventfd, const char *args)
{
struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp);
- struct mem_cgroup_threshold_ary *thresholds, *thresholds_new;
+ struct mem_cgroup_thresholds *thresholds;
+ struct mem_cgroup_threshold_ary *new;
int type = MEMFILE_TYPE(cft->private);
u64 threshold, usage;
- int size;
- int i, ret;
+ int i, size, ret;
ret = res_counter_memparse_write_strategy(args, &threshold);
if (ret)
return ret;
mutex_lock(&memcg->thresholds_lock);
+
if (type == _MEM)
- thresholds = memcg->thresholds;
+ thresholds = &memcg->thresholds;
else if (type == _MEMSWAP)
- thresholds = memcg->memsw_thresholds;
+ thresholds = &memcg->memsw_thresholds;
else
BUG();
usage = mem_cgroup_usage(memcg, type == _MEMSWAP);
/* Check if a threshold crossed before adding a new one */
- if (thresholds)
+ if (thresholds->primary)
__mem_cgroup_threshold(memcg, type == _MEMSWAP);
- if (thresholds)
- size = thresholds->size + 1;
- else
- size = 1;
+ size = thresholds->primary ? thresholds->primary->size + 1 : 1;
/* Allocate memory for new array of thresholds */
- thresholds_new = kmalloc(sizeof(*thresholds_new) +
- size * sizeof(struct mem_cgroup_threshold),
+ new = kmalloc(sizeof(*new) + size * sizeof(struct mem_cgroup_threshold),
GFP_KERNEL);
- if (!thresholds_new) {
+ if (!new) {
ret = -ENOMEM;
goto unlock;
}
- thresholds_new->size = size;
+ new->size = size;
/* Copy thresholds (if any) to new array */
- if (thresholds)
- memcpy(thresholds_new->entries, thresholds->entries,
- thresholds->size *
+ if (thresholds->primary) {
+ memcpy(new->entries, thresholds->primary->entries, (size - 1) *
sizeof(struct mem_cgroup_threshold));
+ }
+
/* Add new threshold */
- thresholds_new->entries[size - 1].eventfd = eventfd;
- thresholds_new->entries[size - 1].threshold = threshold;
+ new->entries[size - 1].eventfd = eventfd;
+ new->entries[size - 1].threshold = threshold;
/* Sort thresholds. Registering of new threshold isn't time-critical */
- sort(thresholds_new->entries, size,
- sizeof(struct mem_cgroup_threshold),
+ sort(new->entries, size, sizeof(struct mem_cgroup_threshold),
compare_thresholds, NULL);
/* Find current threshold */
- atomic_set(&thresholds_new->current_threshold, -1);
+ new->current_threshold = -1;
for (i = 0; i < size; i++) {
- if (thresholds_new->entries[i].threshold < usage) {
+ if (new->entries[i].threshold < usage) {
/*
- * thresholds_new->current_threshold will not be used
- * until rcu_assign_pointer(), so it's safe to increment
+ * new->current_threshold will not be used until
+ * rcu_assign_pointer(), so it's safe to increment
* it here.
*/
- atomic_inc(&thresholds_new->current_threshold);
+ ++new->current_threshold;
}
}
- if (type == _MEM)
- rcu_assign_pointer(memcg->thresholds, thresholds_new);
- else
- rcu_assign_pointer(memcg->memsw_thresholds, thresholds_new);
+ /* Free old spare buffer and save old primary buffer as spare */
+ kfree(thresholds->spare);
+ thresholds->spare = thresholds->primary;
- /* To be sure that nobody uses thresholds before freeing it */
+ rcu_assign_pointer(thresholds->primary, new);
+
+ /* To be sure that nobody uses thresholds */
synchronize_rcu();
- kfree(thresholds);
unlock:
mutex_unlock(&memcg->thresholds_lock);
return ret;
}
-static int mem_cgroup_unregister_event(struct cgroup *cgrp, struct cftype *cft,
- struct eventfd_ctx *eventfd)
+static void mem_cgroup_usage_unregister_event(struct cgroup *cgrp,
+ struct cftype *cft, struct eventfd_ctx *eventfd)
{
struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp);
- struct mem_cgroup_threshold_ary *thresholds, *thresholds_new;
+ struct mem_cgroup_thresholds *thresholds;
+ struct mem_cgroup_threshold_ary *new;
int type = MEMFILE_TYPE(cft->private);
u64 usage;
- int size = 0;
- int i, j, ret;
+ int i, j, size;
mutex_lock(&memcg->thresholds_lock);
if (type == _MEM)
- thresholds = memcg->thresholds;
+ thresholds = &memcg->thresholds;
else if (type == _MEMSWAP)
- thresholds = memcg->memsw_thresholds;
+ thresholds = &memcg->memsw_thresholds;
else
BUG();
__mem_cgroup_threshold(memcg, type == _MEMSWAP);
/* Calculate new number of threshold */
- for (i = 0; i < thresholds->size; i++) {
- if (thresholds->entries[i].eventfd != eventfd)
+ size = 0;
+ for (i = 0; i < thresholds->primary->size; i++) {
+ if (thresholds->primary->entries[i].eventfd != eventfd)
size++;
}
+ new = thresholds->spare;
+
/* Set thresholds array to NULL if we don't have thresholds */
if (!size) {
- thresholds_new = NULL;
- goto assign;
+ kfree(new);
+ new = NULL;
+ goto swap_buffers;
}
- /* Allocate memory for new array of thresholds */
- thresholds_new = kmalloc(sizeof(*thresholds_new) +
- size * sizeof(struct mem_cgroup_threshold),
- GFP_KERNEL);
- if (!thresholds_new) {
- ret = -ENOMEM;
- goto unlock;
- }
- thresholds_new->size = size;
+ new->size = size;
/* Copy thresholds and find current threshold */
- atomic_set(&thresholds_new->current_threshold, -1);
- for (i = 0, j = 0; i < thresholds->size; i++) {
- if (thresholds->entries[i].eventfd == eventfd)
+ new->current_threshold = -1;
+ for (i = 0, j = 0; i < thresholds->primary->size; i++) {
+ if (thresholds->primary->entries[i].eventfd == eventfd)
continue;
- thresholds_new->entries[j] = thresholds->entries[i];
- if (thresholds_new->entries[j].threshold < usage) {
+ new->entries[j] = thresholds->primary->entries[i];
+ if (new->entries[j].threshold < usage) {
/*
- * thresholds_new->current_threshold will not be used
+ * new->current_threshold will not be used
* until rcu_assign_pointer(), so it's safe to increment
* it here.
*/
- atomic_inc(&thresholds_new->current_threshold);
+ ++new->current_threshold;
}
j++;
}
-assign:
- if (type == _MEM)
- rcu_assign_pointer(memcg->thresholds, thresholds_new);
- else
- rcu_assign_pointer(memcg->memsw_thresholds, thresholds_new);
+swap_buffers:
+ /* Swap primary and spare array */
+ thresholds->spare = thresholds->primary;
+ rcu_assign_pointer(thresholds->primary, new);
- /* To be sure that nobody uses thresholds before freeing it */
+ /* To be sure that nobody uses thresholds */
synchronize_rcu();
- kfree(thresholds);
-unlock:
mutex_unlock(&memcg->thresholds_lock);
+}
- return ret;
+static int mem_cgroup_oom_register_event(struct cgroup *cgrp,
+ struct cftype *cft, struct eventfd_ctx *eventfd, const char *args)
+{
+ struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp);
+ struct mem_cgroup_eventfd_list *event;
+ int type = MEMFILE_TYPE(cft->private);
+
+ BUG_ON(type != _OOM_TYPE);
+ event = kmalloc(sizeof(*event), GFP_KERNEL);
+ if (!event)
+ return -ENOMEM;
+
+ mutex_lock(&memcg_oom_mutex);
+
+ event->eventfd = eventfd;
+ list_add(&event->list, &memcg->oom_notify);
+
+ /* already in OOM ? */
+ if (atomic_read(&memcg->oom_lock))
+ eventfd_signal(eventfd, 1);
+ mutex_unlock(&memcg_oom_mutex);
+
+ return 0;
+}
+
+static void mem_cgroup_oom_unregister_event(struct cgroup *cgrp,
+ struct cftype *cft, struct eventfd_ctx *eventfd)
+{
+ struct mem_cgroup *mem = mem_cgroup_from_cont(cgrp);
+ struct mem_cgroup_eventfd_list *ev, *tmp;
+ int type = MEMFILE_TYPE(cft->private);
+
+ BUG_ON(type != _OOM_TYPE);
+
+ mutex_lock(&memcg_oom_mutex);
+
+ list_for_each_entry_safe(ev, tmp, &mem->oom_notify, list) {
+ if (ev->eventfd == eventfd) {
+ list_del(&ev->list);
+ kfree(ev);
+ }
+ }
+
+ mutex_unlock(&memcg_oom_mutex);
+}
+
+static int mem_cgroup_oom_control_read(struct cgroup *cgrp,
+ struct cftype *cft, struct cgroup_map_cb *cb)
+{
+ struct mem_cgroup *mem = mem_cgroup_from_cont(cgrp);
+
+ cb->fill(cb, "oom_kill_disable", mem->oom_kill_disable);
+
+ if (atomic_read(&mem->oom_lock))
+ cb->fill(cb, "under_oom", 1);
+ else
+ cb->fill(cb, "under_oom", 0);
+ return 0;
+}
+
+static int mem_cgroup_oom_control_write(struct cgroup *cgrp,
+ struct cftype *cft, u64 val)
+{
+ struct mem_cgroup *mem = mem_cgroup_from_cont(cgrp);
+ struct mem_cgroup *parent;
+
+ /* cannot set to root cgroup and only 0 and 1 are allowed */
+ if (!cgrp->parent || !((val == 0) || (val == 1)))
+ return -EINVAL;
+
+ parent = mem_cgroup_from_cont(cgrp->parent);
+
+ cgroup_lock();
+ /* oom-kill-disable is a flag for subhierarchy. */
+ if ((parent->use_hierarchy) ||
+ (mem->use_hierarchy && !list_empty(&cgrp->children))) {
+ cgroup_unlock();
+ return -EINVAL;
+ }
+ mem->oom_kill_disable = val;
+ if (!val)
+ memcg_oom_recover(mem);
+ cgroup_unlock();
+ return 0;
}
static struct cftype mem_cgroup_files[] = {
.name = "usage_in_bytes",
.private = MEMFILE_PRIVATE(_MEM, RES_USAGE),
.read_u64 = mem_cgroup_read,
- .register_event = mem_cgroup_register_event,
- .unregister_event = mem_cgroup_unregister_event,
+ .register_event = mem_cgroup_usage_register_event,
+ .unregister_event = mem_cgroup_usage_unregister_event,
},
{
.name = "max_usage_in_bytes",
.read_u64 = mem_cgroup_move_charge_read,
.write_u64 = mem_cgroup_move_charge_write,
},
+ {
+ .name = "oom_control",
+ .read_map = mem_cgroup_oom_control_read,
+ .write_u64 = mem_cgroup_oom_control_write,
+ .register_event = mem_cgroup_oom_register_event,
+ .unregister_event = mem_cgroup_oom_unregister_event,
+ .private = MEMFILE_PRIVATE(_OOM_TYPE, OOM_CONTROL),
+ },
};
#ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
.name = "memsw.usage_in_bytes",
.private = MEMFILE_PRIVATE(_MEMSWAP, RES_USAGE),
.read_u64 = mem_cgroup_read,
- .register_event = mem_cgroup_register_event,
- .unregister_event = mem_cgroup_unregister_event,
+ .register_event = mem_cgroup_usage_register_event,
+ .unregister_event = mem_cgroup_usage_unregister_event,
},
{
.name = "memsw.max_usage_in_bytes",
*/
if (!node_state(node, N_NORMAL_MEMORY))
tmp = -1;
- pn = kmalloc_node(sizeof(*pn), GFP_KERNEL, tmp);
+ pn = kzalloc_node(sizeof(*pn), GFP_KERNEL, tmp);
if (!pn)
return 1;
mem->info.nodeinfo[node] = pn;
- memset(pn, 0, sizeof(*pn));
-
for (zone = 0; zone < MAX_NR_ZONES; zone++) {
mz = &pn->zoneinfo[zone];
for_each_lru(l)
/* Can be very big if MAX_NUMNODES is very big */
if (size < PAGE_SIZE)
- mem = kmalloc(size, GFP_KERNEL);
+ mem = kzalloc(size, GFP_KERNEL);
else
- mem = vmalloc(size);
+ mem = vzalloc(size);
if (!mem)
return NULL;
- memset(mem, 0, size);
mem->stat = alloc_percpu(struct mem_cgroup_stat_cpu);
- if (!mem->stat) {
- if (size < PAGE_SIZE)
- kfree(mem);
- else
- vfree(mem);
- mem = NULL;
- }
+ if (!mem->stat)
+ goto out_free;
+ spin_lock_init(&mem->pcp_counter_lock);
return mem;
+
+out_free:
+ if (size < PAGE_SIZE)
+ kfree(mem);
+ else
+ vfree(mem);
+ return NULL;
}
/*
&per_cpu(memcg_stock, cpu);
INIT_WORK(&stock->work, drain_local_stock);
}
- hotcpu_notifier(memcg_stock_cpu_callback, 0);
+ hotcpu_notifier(memcg_cpu_hotplug_callback, 0);
} else {
parent = mem_cgroup_from_cont(cont->parent);
mem->use_hierarchy = parent->use_hierarchy;
+ mem->oom_kill_disable = parent->oom_kill_disable;
}
if (parent && parent->use_hierarchy) {
}
mem->last_scanned_child = 0;
spin_lock_init(&mem->reclaim_param_lock);
+ INIT_LIST_HEAD(&mem->oom_notify);
if (parent)
mem->swappiness = get_swappiness(parent);
goto one_by_one;
}
mc.precharge += count;
- VM_BUG_ON(test_bit(CSS_ROOT, &mem->css.flags));
- WARN_ON_ONCE(count > INT_MAX);
- __css_get(&mem->css, (int)count);
return ret;
}
one_by_one:
batch_count = PRECHARGE_COUNT_AT_ONCE;
cond_resched();
}
- ret = __mem_cgroup_try_charge(NULL, GFP_KERNEL, &mem, false);
+ ret = __mem_cgroup_try_charge(NULL, GFP_KERNEL, &mem, false,
+ PAGE_SIZE);
if (ret || !mem)
/* mem_cgroup_clear_mc() will do uncharge later */
return -ENOMEM;
MC_TARGET_SWAP,
};
+static struct page *mc_handle_present_pte(struct vm_area_struct *vma,
+ unsigned long addr, pte_t ptent)
+{
+ struct page *page = vm_normal_page(vma, addr, ptent);
+
+ if (!page || !page_mapped(page))
+ return NULL;
+ if (PageAnon(page)) {
+ /* we don't move shared anon */
+ if (!move_anon() || page_mapcount(page) > 2)
+ return NULL;
+ } else if (!move_file())
+ /* we ignore mapcount for file pages */
+ return NULL;
+ if (!get_page_unless_zero(page))
+ return NULL;
+
+ return page;
+}
+
+static struct page *mc_handle_swap_pte(struct vm_area_struct *vma,
+ unsigned long addr, pte_t ptent, swp_entry_t *entry)
+{
+ int usage_count;
+ struct page *page = NULL;
+ swp_entry_t ent = pte_to_swp_entry(ptent);
+
+ if (!move_anon() || non_swap_entry(ent))
+ return NULL;
+ usage_count = mem_cgroup_count_swap_user(ent, &page);
+ if (usage_count > 1) { /* we don't move shared anon */
+ if (page)
+ put_page(page);
+ return NULL;
+ }
+ if (do_swap_account)
+ entry->val = ent.val;
+
+ return page;
+}
+
+static struct page *mc_handle_file_pte(struct vm_area_struct *vma,
+ unsigned long addr, pte_t ptent, swp_entry_t *entry)
+{
+ struct page *page = NULL;
+ struct inode *inode;
+ struct address_space *mapping;
+ pgoff_t pgoff;
+
+ if (!vma->vm_file) /* anonymous vma */
+ return NULL;
+ if (!move_file())
+ return NULL;
+
+ inode = vma->vm_file->f_path.dentry->d_inode;
+ mapping = vma->vm_file->f_mapping;
+ if (pte_none(ptent))
+ pgoff = linear_page_index(vma, addr);
+ else /* pte_file(ptent) is true */
+ pgoff = pte_to_pgoff(ptent);
+
+ /* page is moved even if it's not RSS of this task(page-faulted). */
+ if (!mapping_cap_swap_backed(mapping)) { /* normal file */
+ page = find_get_page(mapping, pgoff);
+ } else { /* shmem/tmpfs file. we should take account of swap too. */
+ swp_entry_t ent;
+ mem_cgroup_get_shmem_target(inode, pgoff, &page, &ent);
+ if (do_swap_account)
+ entry->val = ent.val;
+ }
+
+ return page;
+}
+
static int is_target_pte_for_mc(struct vm_area_struct *vma,
unsigned long addr, pte_t ptent, union mc_target *target)
{
struct page_cgroup *pc;
int ret = 0;
swp_entry_t ent = { .val = 0 };
- int usage_count = 0;
- bool move_anon = test_bit(MOVE_CHARGE_TYPE_ANON,
- &mc.to->move_charge_at_immigrate);
- if (!pte_present(ptent)) {
- /* TODO: handle swap of shmes/tmpfs */
- if (pte_none(ptent) || pte_file(ptent))
- return 0;
- else if (is_swap_pte(ptent)) {
- ent = pte_to_swp_entry(ptent);
- if (!move_anon || non_swap_entry(ent))
- return 0;
- usage_count = mem_cgroup_count_swap_user(ent, &page);
- }
- } else {
- page = vm_normal_page(vma, addr, ptent);
- if (!page || !page_mapped(page))
- return 0;
- /*
- * TODO: We don't move charges of file(including shmem/tmpfs)
- * pages for now.
- */
- if (!move_anon || !PageAnon(page))
- return 0;
- if (!get_page_unless_zero(page))
- return 0;
- usage_count = page_mapcount(page);
- }
- if (usage_count > 1) {
- /*
- * TODO: We don't move charges of shared(used by multiple
- * processes) pages for now.
- */
- if (page)
- put_page(page);
+ if (pte_present(ptent))
+ page = mc_handle_present_pte(vma, addr, ptent);
+ else if (is_swap_pte(ptent))
+ page = mc_handle_swap_pte(vma, addr, ptent, &ent);
+ else if (pte_none(ptent) || pte_file(ptent))
+ page = mc_handle_file_pte(vma, addr, ptent, &ent);
+
+ if (!page && !ent.val)
return 0;
- }
if (page) {
pc = lookup_page_cgroup(page);
/*
if (!ret || !target)
put_page(page);
}
- /* throught */
- if (ent.val && do_swap_account && !ret &&
+ /* There is a swap entry and a page doesn't exist or isn't charged */
+ if (ent.val && !ret &&
css_id(&mc.from->css) == lookup_swap_cgroup(ent)) {
ret = MC_TARGET_SWAP;
if (target)
pte_t *pte;
spinlock_t *ptl;
+ VM_BUG_ON(pmd_trans_huge(*pmd));
pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
for (; addr != end; pte++, addr += PAGE_SIZE)
if (is_target_pte_for_mc(vma, addr, *pte, NULL))
};
if (is_vm_hugetlb_page(vma))
continue;
- /* TODO: We don't move charges of shmem/tmpfs pages for now. */
- if (vma->vm_flags & VM_SHARED)
- continue;
walk_page_range(vma->vm_start, vma->vm_end,
&mem_cgroup_count_precharge_walk);
}
static int mem_cgroup_precharge_mc(struct mm_struct *mm)
{
- return mem_cgroup_do_precharge(mem_cgroup_count_precharge(mm));
+ unsigned long precharge = mem_cgroup_count_precharge(mm);
+
+ VM_BUG_ON(mc.moving_task);
+ mc.moving_task = current;
+ return mem_cgroup_do_precharge(precharge);
}
-static void mem_cgroup_clear_mc(void)
+/* cancels all extra charges on mc.from and mc.to, and wakes up all waiters. */
+static void __mem_cgroup_clear_mc(void)
{
+ struct mem_cgroup *from = mc.from;
+ struct mem_cgroup *to = mc.to;
+
/* we must uncharge all the leftover precharges from mc.to */
if (mc.precharge) {
__mem_cgroup_cancel_charge(mc.to, mc.precharge);
}
/* we must fixup refcnts and charges */
if (mc.moved_swap) {
- WARN_ON_ONCE(mc.moved_swap > INT_MAX);
/* uncharge swap account from the old cgroup */
if (!mem_cgroup_is_root(mc.from))
res_counter_uncharge(&mc.from->memsw,
*/
res_counter_uncharge(&mc.to->res,
PAGE_SIZE * mc.moved_swap);
- VM_BUG_ON(test_bit(CSS_ROOT, &mc.to->css.flags));
- __css_put(&mc.to->css, mc.moved_swap);
}
/* we've already done mem_cgroup_get(mc.to) */
-
mc.moved_swap = 0;
}
+ memcg_oom_recover(from);
+ memcg_oom_recover(to);
+ wake_up_all(&mc.waitq);
+}
+
+static void mem_cgroup_clear_mc(void)
+{
+ struct mem_cgroup *from = mc.from;
+
+ /*
+ * we must clear moving_task before waking up waiters at the end of
+ * task migration.
+ */
+ mc.moving_task = NULL;
+ __mem_cgroup_clear_mc();
+ spin_lock(&mc.lock);
mc.from = NULL;
mc.to = NULL;
- mc.moving_task = NULL;
- wake_up_all(&mc.waitq);
+ spin_unlock(&mc.lock);
+ mem_cgroup_end_move(from);
}
static int mem_cgroup_can_attach(struct cgroup_subsys *ss,
VM_BUG_ON(mc.precharge);
VM_BUG_ON(mc.moved_charge);
VM_BUG_ON(mc.moved_swap);
- VM_BUG_ON(mc.moving_task);
+ mem_cgroup_start_move(from);
+ spin_lock(&mc.lock);
mc.from = from;
mc.to = mem;
- mc.precharge = 0;
- mc.moved_charge = 0;
- mc.moved_swap = 0;
- mc.moving_task = current;
+ spin_unlock(&mc.lock);
+ /* We set mc.moving_task later */
ret = mem_cgroup_precharge_mc(mm);
if (ret)
spinlock_t *ptl;
retry:
+ VM_BUG_ON(pmd_trans_huge(*pmd));
pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
for (; addr != end; addr += PAGE_SIZE) {
pte_t ptent = *(pte++);
goto put;
pc = lookup_page_cgroup(page);
if (!mem_cgroup_move_account(pc,
- mc.from, mc.to, false)) {
+ mc.from, mc.to, false, PAGE_SIZE)) {
mc.precharge--;
/* we uncharge from mc.from later. */
mc.moved_charge++;
struct vm_area_struct *vma;
lru_add_drain_all();
- down_read(&mm->mmap_sem);
+retry:
+ if (unlikely(!down_read_trylock(&mm->mmap_sem))) {
+ /*
+ * Someone who are holding the mmap_sem might be waiting in
+ * waitq. So we cancel all extra charges, wake up all waiters,
+ * and retry. Because we cancel precharges, we might not be able
+ * to move enough charges, but moving charge is a best-effort
+ * feature anyway, so it wouldn't be a big problem.
+ */
+ __mem_cgroup_clear_mc();
+ cond_resched();
+ goto retry;
+ }
for (vma = mm->mmap; vma; vma = vma->vm_next) {
int ret;
struct mm_walk mem_cgroup_move_charge_walk = {
};
if (is_vm_hugetlb_page(vma))
continue;
- /* TODO: We don't move charges of shmem/tmpfs pages for now. */
- if (vma->vm_flags & VM_SHARED)
- continue;
ret = walk_page_range(vma->vm_start, vma->vm_end,
&mem_cgroup_move_charge_walk);
if (ret)
};
#ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
+static int __init enable_swap_account(char *s)
+{
+ /* consider enabled if no parameter or 1 is given */
+ if (!(*s) || !strcmp(s, "=1"))
+ really_do_swap_account = 1;
+ else if (!strcmp(s, "=0"))
+ really_do_swap_account = 0;
+ return 1;
+}
+__setup("swapaccount", enable_swap_account);
static int __init disable_swap_account(char *s)
{
- really_do_swap_account = 0;
+ printk_once("noswapaccount is deprecated and will be removed in 2.6.40. Use swapaccount=0 instead\n");
+ enable_swap_account("=0");
return 1;
}
__setup("noswapaccount", disable_swap_account);
projects / linux-flexiantxendom0-natty.git / blobdiff